Kids, help your parents if they don't know how to use a smartphone.

The honor you have given us goes not to us as a crew, but to ... all Americans, who believed, who persevered with us. What Apollo has begun we hope will spread out in many directions, not just in space, but underneath the seas, and in the cities to tell us unforgettably what we will and must do. There are footprints on the moon. Those footprints belong to each and every one of you, to all mankind. They are there because of the blood, sweat, and tears of millions of people. Those footprints are the symbol of true human spirit.

I'm sure that there are places in the deserts in Australia that could be similar to where we might want to go on Mars.

We can't start over and develop a Saturn 5-type vehicle from scratch.

The energy varies with the square of the velocity, so if you need five times the velocity, that's 25 times the energy.

The feeling of reduced gravity and the limitations of the space suit resulted in a slow-motion movement. Perhaps not too far from a trampoline, but without the springiness and instability.

NASA needs to focus on the things that are really important and that we do not know how to do. The agency is a pioneering force, and that is where its competitive advantage lies.